The present invention relates to building construction, and more particularly to plumbing fixtures used to mount water pipe to studs or joists.
Copper water pipe should not be supported over long distances by extending through holes drilled in studs. Such holes are time consuming to drill and weaken the strength of the studs. Also, water hammer in the pipe can cause the pipe to move in the studs since the holes are typically larger than the outside diameter of the pipe.
A large number of pipe hanging clamps have been developed in the past for supporting thin walled copper water pipe in building constructions. These clamps need to accommodate thermal expansion of the copper pipe. The clamps should not be made of dissimilar metal since galvanic action can cause corrosion.
The following is a list of U.S. patents showing various clamps and hangers in this field:
U.S. Pat. No. 2,216,886--Titled: Holder--Langelier PA1 U.S. Pat. No. 2,992,800--Titled: Pipe Hanger--Madson PA1 U.S. Pat. No. 3,503,580--Titled: Universal Conduit Support Bracket--Levy PA1 U.S. Pat. No. 3,684,223--Titled: Pipe Clamp--Logsdon PA1 U.S. Pat. No. 4,369,945--Titled: Cable Clamps--Mantoan et al. PA1 U.S. Pat. No. 4,379,537--Titled: Cable Hanger--Perrault et al. PA1 U.S. Pat. No. 4,714,218--Titled: Hanger for Pipe Clamp--Hungerford, Jr.
More recently it has been common to surround the pipe with clamps hung on straps nailed between studs. Strap material of this type is widel,; used and is sold under the trademark HYCO. It has holes punched in the center at regular intervals.
Of the foregoing patented devices, the pipe clamp of U.S. Pat. No. 3,684,223 of Logsdon has been widely used by plumbers. However, it must either be nailed to a stud or secured with screws or bolts to a HYCO strap, which adds time and cost to the plumbing installation.
The pipe hanging clamp disclosed in U.S. Pat. No. 5,024,405 of McGuire has a central peg and two other pegs on either side of the central peg. This device can be rotated into engagement with corresponding holes in a HYCO strap. The principal drawback of this device is that the holes in the HYCO strap are not precision drilled and the pegs are not precisely located on the clamp due to tolerance variations in the injection molding. Therefore it is sometimes difficult, if not impossible, to align the pegs with a pair of holes in the HYCO strap. Also, removal of the McGuire device from the HYCO strap once it has been snapped into place is extremely difficult. This makes it hard to re-mount the clamp if the plumber misjudges the initial location for the pipe mounting. Additionally, the McGuire device requires two steps, namely, mounting the device onto the strap and then squeezing the mating ratchet and pawl portions together around the pipe. Plumbers frequently squeeze the pipe too tightly and the plastic parts fatigue. Also, the ratchet and pawl sometimes break away from the base portion of the McGuire device.
The HOLD-RITE device manufactured by Hubbard Enterprises permits a water pipe to be soldered to a metal strap having alternating larger and smaller holes. See U.S. Pat. No. 4,550,451.
In my U.S. Pat. No. 5,154,375 granted Oct. 13, 1992 entitled PIPE HANGING CLAMP there is described a unitary injection molded plastic clamp for easily and rapidly attaching copper pipe to HYCO strap so that the pipe extends perpendicular to the plane of the strap. In my co-pending U.S. patent application Ser. No. 07/913,154 filed Jul. 14, 1992 entitled CLIP-ON PIPE HANGING CLAMP there is described another unitary injection molded plastic clamp for easily and rapidly attaching copper pipe to HYCO strap so that the pipe extends in the plane of the strap.
While my aforementioned injection molded plastic pipe hanging clamps represent significant improvements over the aforementioned prior art pipe hanging clamps, there are some applications where it is necessary to solder the copper pipe to a hanger which is attached to a segment of HYCO strap. For example, a stub out for a hose bib must be securely attached to HYCO strap in such a manner that it is virtually impossible to pull it out. Also, in some applications, it is necessary that a pipe be mounted so that there is absolutely no capability for movement of the pipe due to, for example, water hammer. My aforementioned plastic pipe hanging clamps permit a minor degree of flex or movement and with sufficient force, a pipe mounted with the same could be torn away from the HYCO strap, e.g. by excessive manual pulling.